This invention relates to the treatment or prevention of carpal tunnel syndrome and, in particular, to a bracelet-like appliance for opening the carpal canal by stretching the transverse carpal ligament and the surrounding structure of the hand, wrist, and forearm of a person.
"Carpal Tunnel Syndrome" is the result of a compromised or narrowed carpal canal leading to compression injury of the median nerve in the wrist. The carpal tunnel is the canal in the wrist through which the median nerve and flexor tendons pass from the forearm to the hand. Prolonged, repetitive motion at a keyboard is a common, but by no means the only, cause of the syndrome.
To date, carpal tunnel syndrome has been treated with wrist rests, anti-inflammatory medications, cortisone injections, surgery, or orthoses, such as wrist splints. Alone or combined, these treatments have met with varying degrees of success. The obvious solution, removing the cause of the injury, is not always practical since, as in the case of using a keyboard, the cause of the injury is often the means by which the patient obtains his or her livelihood. The next best choice, prevention through proper preparation, can be achieved by enlarging the carpal canal to maintain adequate space for the median nerve and thus avoid compression.
The carpal canal can be enlarged by osteopathic manipulation and stretching, thereby alleviating compression on the median nerve and resolving carpal tunnel syndrome. While severe cases may require other treatment, manipulation is effective in the majority of cases and has the advantage of being prophylactic, i.e. a preventative.
While manipulation and stretching are effective, there are two difficulties. Optimum resolution of the symptoms requires frequent stretching and the assistance of another person, a physician to perform the manipulation. There is a need for an appliance which a patient can use to augment treatment by the physician. It is known from studies of rehabilitated knee joints and elbow joints that the longest period of low force stretching produces the greatest amount of permanent elongation of connective tissue. Ideally, the stretching would be accomplished by means of an appliance which is adjusted by the physician to provide the appropriate force for stretching, preferably continuously.
Simply prescribing the use of an appliance does not mean that the patient will use it properly. If a patient is expected to put on and remove an appliance, a properly adjusted appliance must not be able to be put on incorrectly or to inflict either too much or too little stretching. Proper use also refers to the compliance or self-discipline of the patient and how easy it is to use the appliance. In general, an appliance that is mechanically simple, easy to use, and comfortable to wear will more likely be used as directed.
The skin is sensitive to long term pressure, which can cause a localized loss of circulation and lead to ulceration. Obviously, a patient will not be comfortable if an appliance causes such irritation. On the other hand, sufficient pressure must be applied in order to be effective.
An appliance must also be comfortable in the sense that it does not interfere with the function of the arm, wrist, and hand. Otherwise, a patient is unlikely to wear the appliance long enough to be fully effective, preferably overnight, or when performing routine tasks which may irritate the median nerve. An appliance duplicating the manipulation by a physician would obviously interfere with the patient's use of the hand. What is desired is an appliance which duplicates as much of the physician's treatment as possible without interfering with the use of the arm, wrist, and hand.
In view of the foregoing, it is therefore an object of the invention to provide a bracelet-like appliance for treating or preventing carpal tunnel syndrome.
Another object of the invention is to provide a mechanically simple, easily used, comfortable appliance for treating or preventing carpal tunnel syndrome.
A further object of the invention is to provide an appliance for relieving the pressure on the median nerve by stretching the transverse carpal ligament and the related or associated structures of the wrist.
Another object of the invention is to provide an appliance which will provide a continuous, gentle pressure for elongating the transverse carpal ligament.
A further object of the invention is to provide an appliance which can be worn continuously despite the fact that the appliance exerts pressure at several locations on the wrist.
Another object of the invention is to provide a bracelet-like appliance for treating or preventing carpal tunnel syndrome wherein the appliance does not impair the function of the arm, wrist, and hand.